import copy
n,m = map(int,input().split())

s = [chr(ord('A')+i) for i in range(26)]
for i in range(n):
    cnt = 0
    
    h=i
    while h>=1:
        print("{}".format(s[h]),end='')
        h-=1
        cnt += 1
        if cnt>=m:
            break

    if cnt<m:
        b = m-i
        for j in range(b):
            print("{}".format(s[j]),end='')
            cnt += 1
            if cnt>=m:
                break

    print()





    
